T520, battery and charger doubts.

[aeternal]

Where I live there are just two configurations available for the Thinkpad t520 and they are:

They are both thinkpad t520 4243:

Product Description: Lenovo ThinkPad T520 4243 - Core i7 2620M 2.7 GHz - 15.6" TFT
Weight: 2.7 kg
Localisation: English, German, French, Italian / Switzerland
Processor: Intel Core i7 2620M / 2.7 GHz ( 3.4 GHz ) ( Dual-Core )
RAM: 4 GB (installed) / 8 GB (max) - DDR3 SDRAM - 1333 MHz - PC3-10600 ( 1 x 4 GB )
Hard Drive: 500 GB - Serial ATA-300 - 7200 rpm
Optical Storage: DVD-Writer - removable plug-in module
Display: 15.6" LED backlight TFT 1600 x 900 ( WXGA++ ) - 16:9
Graphics Controller: NVIDIA NVS 4200M / Intel HD Graphics 3000
Video Memory: 1 GB
Audio Output: Sound card
Wireless NIC: Intel Centrino Ultimate-N 6300
Input Device: Keyboard, TrackPoint, UltraNav
Power: AC 120/230 V ( 50/60 Hz )
Manufacturer Warranty: 3 years warranty

their only difference is the battery. Actually, one of them has a 6 cells battery with a 65W power brick. The other has by default a 9 Cells battery and a 90W power brick.
Let's assume I will buy the 6 Cells one, and let's assume someday I will decide to buy a 9 cells battery. Would the 65W power brick be still enough to power up the battery during work? Or even if I am charging the laptop during work I will see the battery getting down? And more importantly, is the 65W power brick compatible with the 9 cells battery and vice versa? (namely, the 90W power brick with the 6 cells battery). Because I would like to avoid to buy a new battery and have to change the power brick too.

Besides that, I noticed another thing. In the informations given by the shop (official lenovo online shop), that laptop using the 6 Cells battery they say it has 7.7h of autonomy. For the 9 cells they say 14h. I know that these are mere internal tests, but could it be actually possible a similar autonomy's difference between them? (remember that the configuration is the same)

Do you have any different infos about its autonomy (either 6 and 9 cells) during a low-medium work?

Thanks for the support.


EDIT: just wondering, the 9 cells battery sticks out? If yes, from the bottom or from the rear? The website doesn't say anything.

[Harryc]

Using an AC adapter with a lower Watt rating than what Lenovo recommends may result in slower charging times for the 9 cell, and/or reduced performance due to downclocking by Power Management. The 9 cell sticks out the back of the machine less than 1 inch. 90 watt adapters are very inexpensive....why not get one when you get a 9 cell?

[TTY]

The difference between the two models is probably not only the battery, but also the built-in graphics chip. Models with Intel chipset graphics usually have a 65 W AC adapter, models with other graphics chips use 90 W AC adapters. The AC adapters' power rating has nothing to do with battery capacity. A 65 W AC adapter can charge a 9 cell battery without problems. The specs that you posted are for a notebook that has two different graphics chips and can switch between these chips depending on load. That technology is called nVIDIA Optimus. T520 models with nVIDIA Optimus graphics come with a 90 W AC adapter.

[Harryc]

The OP said the only difference is the battery...also a 65w adapter WILL charge a battery slower in a system that calls for a 90w adapter.

[TTY]

The OP said the only difference is the battery

Yes, but as this was the first time that i read that different batteries would need different AC adapters, i checked what Lenovo offers on their Swiss site. They offer three T520 models, two of them have the i7 2620M processor. One of these two models has the Intel HD Graphics 3000, the other one has the Intel HD Graphics 3000 and the NVIDIA NVS 4200M (Optimus). The first comes with a 65 W adapter, the second one comes with a 90 W adapter.

[Colonel O'Neill]

It's always okay to use a 90W where a 65W is needed, but it'd lead to reduced performance when a 65W is used where a 90W is needed.

Batteries can vary independently of the adapter used.

[aeternal]

You are right, I didn't noticed that one had not the discrete. Thanks a lot, without your tip I would probably buy it. But if it hasn't the discrete then the 9 cells will be definitely the one that I need.

Just one more thing, if I buy a case sleeve, like this one:

http://www.shoplenovo.ch/it/products/93 ... ase-sleeve

I will have problems by closing it with the battery sticking out? Or even if it is 1 inch longer, it still closes normally?

Thanks a lot, I appreciate your help

[TTY]

The sleeve is 30 cm deep and 2.5 cm high, the T520 with a 9 cell is 26.8 cm deep and 3.6 cm high. Although the empty sleeve has a little bit less height than the notebook, i suppose the sleeve will be able to accommodate the notebook, even with a 9 cell battery.

[TTY]

In the informations given by the shop (official lenovo online shop), that laptop using the 6 Cells battery they say it has 7.7h of autonomy. For the 9 cells they say 14h. I know that these are mere internal tests, but could it be actually possible a similar autonomy's difference between them? (remember that the configuration is the same)

Do you have any different infos about its autonomy (either 6 and 9 cells) during a low-medium work?

Lenovo's specs (http://www.lenovo.com/psref/pdf/tabook.pdf) say "up to 8.4 h with a 6-cell, and up to 14 h with a 9-cell" for T520 with Optimus. The important part here are the small words "up to". That is, turning up backlight brightness will reduce battery life, an i7 processor might use more power than an i5 processor etc. The numbers that Lenovo presents are probably for a very light workload or idle state.

[redhook]

You are right, I didn't noticed that one had not the discrete. Thanks a lot, without your tip I would probably buy it. But if it hasn't the discrete then the 9 cells will be definitely the one that I need.

Just one more thing, if I buy a case sleeve, like this one:

http://www.shoplenovo.ch/it/products/93 ... ase-sleeve

I will have problems by closing it with the battery sticking out? Or even if it is 1 inch longer, it still closes normally?

Thanks a lot, I appreciate your help

I have that same sleeve and my T510 with 9-cell fits in it perfectly. The sleeve was made for the 9-cell.